(Note: This post has been updated to reflect that the group’s concerts have been cancelled.)

A highly-anticipated appearance in Beijing by North Korean leader Kim Jong Un’s favorite girl band was abruptly cancelled Saturday, hours before the group was set to perform and with no official explanation given.

The Moranbong band’s shows at China’s National Center for the Performing Arts have been cancelled “due to some reasons,” an employee at the venue told China Real Time Saturday night. A person who had a ticket to one of the band’s invitation-only shows confirmed that he received a cancellation notice late Saturday afternoon.

Short hair, glittery miniskirts, electronic pop music and perhaps even the theme song from the 1976 Hollywood hit “Rocky” were expected to grace the stage of Beijing’s top music hall Saturday night as the Moranbong band was set to kick off three days of shows in the Chinese capital.

Hyon Song-wol, the leader of North Korea’s all-female Moranbong Band, arrives at a Beijing hotel on Dec. 11, 2015.

Zuma Press

China’s state-run media lit up with news reports on the group’s visit in recent days, with the official Xinhua News Agency publishing a slideshow showing the women arriving in Beijing dressed in military-style frocks and fur hats.

It was unclear Saturday evening whether the band was still in Beijing. Japan’s Kyodo News Service reported that band members were seen at Beijing’s Capital International Airport and had flown back to Pyongyang late Saturday afternoon. But no updates were forthcoming from Xinhua and other Chinese state-run media.

The visit was to have been the group’s first overseas tour — although no one, it seemed, knew how to obtain a ticket.

Neither the concert venue nor China’s foreign ministry was able to provide instructions on buying a ticket when asked by China Real Time this week.

A ticket agent at the National Centre for the Performing Arts said before Saturday’s cancellations that the performances were being treated as a national-level foreign affairs activity and that the concert hall was responsible only for providing the venue. “We don’t have a single ticket on hand; we even don’t know yet which room will be offered for the performance,” the ticket agent said.

Chinese foreign ministry spokeswoman Hua Chunying said Friday that she had no details on the show or its audience — and had not been invited herself.

”This performance is not organized by the foreign ministry so I have no more information to offer,” she said at a regular briefing. “As for where to buy the tickets, I have no information. I myself have no ticket to the performance.”

Some speculated that the tour was being organized by another official organ, the International Department of the Chinese Communist Party’s Central Committee. Neither that department nor the North Korean Embassy responded to requests for comment.

China has long been North Korea’s economic and diplomatic lifeline. Yet the traditional alliance between the two has come under strain in recent years, particularly after Pyongyang conducted its third nuclear test in 2013 and North Korean forces seized a Chinese fishing boat later that year.

Even so, both countries have played up their ties again since this fall when senior Chinese official Liu Yunshan stood alongside Mr. Kim at a military parade in Pyongyang to mark the 70th anniversary of North Korea’s ruling Workers’ Party. Mr. Liu, who is a member of the Standing Committee of the Chinese Communist Party, also passed along to Mr. Kim a letter from Xi Jinping in which the Chinese president called for closer relations.

Whether Moranbong’s short-lived visit to Beijing was intended to show a further warming of ties between China and North Korea — also known as the Democratic People’s Republic of Korea, or DPRK — remains open to debate. Asked Friday about the group, Ms. Hua called the tour “a major event showing the friendship between the DPRK and China.”

“We believe it contributes to our mutual understanding and the sound and sustainable development of bilateral ties,” she added.

Zhang Yushan, a researcher at the Jilin Social Science Academy who studies North and South Korea, cautioned against reading too much into the visit.

This week, a top United Nations official called for the Security Council to refer North Korea to the International Criminal Court over “gross human rights violations.” China called a vote to stop the meeting, although it failed to halt it.

“North Korea was seeking help from China”, Mr. Zhang of the move. “We are both very practical.”

Members of the Moranbong Band are believed to have been selected by Kim Jong Un himself. The group has become the most well-known girl band in North Korea since its debut in 2012. In addition to anthems urging listeners to “support our supreme commander with arms,” Moranbong’s repertoire also includes a surprising number of foreign pieces, including the “Rocky” theme song and Frank Sinatra’s “My Way.”

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